1. Field of the Invention
The present invention relates to a method and apparatus for spray coating articles of manufacture and, in particular, to improve the doughnut-shaped spray pattern of the atomizer.
2. Description of Prior Art
Heretofore, probes have been used for improving the doughnut-shaped spray pattern, as disclosed in U.S. Pat. No. 2,989,241. In conventional high speed rotary atomizers two sources of air are introduced, a first source for rotating the air vane and a second source for enveloping the paint to produce the spray pattern. The first source of air after exhausting from the air vane merges with the second source of air in the sleeve of the atomizer, so that both sources of air envelope the paint. In such conventional high speed rotary atomizers it has been found that some of the paint and solvent introduced into the atomizer tend to run back from the disc along the spindle shaft and thereby ruin the bearings. Furthermore, the air passing out of the sleeve and around the outer periphery of the disc in enveloping the paint particles produces a doughnut-shaped spray pattern in which the hole thereof is exceedingly large and the body relatively small.